1. Field of the Invention
The present invention relates to a radial line dial plate and an automobile meter provided with the radial line dial plate.
2. Description of the Related Art
There is known an automobile meter which has high-grade feeling in such a manner that a radial line pattern is formed by a plurality of grooves extending radially on some flat surface of a dial plate used in vehicle meters or the like.
For example, a dial plate used in meter devices disclosed in Japanese Patent Application Laid-open No. 2003-4495 is applied with radial line marks made up of a plurality of grooves extending radially from the center of a disk-shaped plate member made of a metal (see paragraphs [0035] and [0040] in the same literature).
In the dial plate made of the metal, however, radial line mark treatment is required to be performed for each sheet of metal plates by a brush, and there are problems in terms of obtaining a uniform quality and in terms of manufacturing costs. In addition, since the dial plate is made of the metal, it is heavy in weight, which is disadvantageous to weight reduction in vehicle, especially.
Therefore, as in display devices or pointer instruments for vehicle disclosed in Japanese Patent Application Laid-open No. 2006-27546 and Japanese Patent Application Laid-open No. 2009-42001, a metallic-tone dial plate has been proposed in which metallic feeling is created using a synthetic resin. Even on the surface of such a metallic-tone dial plate, a radial line pattern is formed which is made up of a plurality of grooves extending radially from a center position corresponding to a rotation center of a pointer of the display device.
However, as in a metallic-tone dial plate illustrated in FIGS. 8A and 8B, a radial line dial plate 501 made of a synthetic resin is configured such that a center 505 of a radial line pattern 503 formed on the surface of the radial line dial plate 501 substantially coincides with a center 507 of a shaft through-hole 502 in an indicator such as a speedometer or a fuel gauge. That is, all of grooves 509 are directed toward the center 507 of the shaft through-hole 502. Therefore, there are problems that the radial line pattern 503 looked non-random and thus uncomfortable feeling occurred in appearance.
Since fine lines such as hairs are linearly given in a hair line process for applying radial line marks to the metal plate, these lines generally intersect with each other. For example, hairline marking is performed on the metal plate when a brush (having a width of about 2 mm) for marking hairlines is stroked while the dial plate is slightly rotated. Accordingly, the stroke mark having a width intersects with a portion of the stroke marks adjacent to each other. In contrast, since the radial line pattern 503 in the radial line dial plate 501 made of the synthetic resin is formed by transferring of a plurality of grooves, which are cut in a molding die and extend radially around one point, to the surface, the radial lines do not intersect with each other. This is considered to cause uncomfortable feeling to metallic feeling of the radial line dial plate 501 made of the synthetic resin.